Illinois - Significance region: Local
| Taylorville Courthouse Square Historic District |
| Tazewell County Courthouse |
| Tegtmeyer Site |
| Terwilliger House |
| The Hunt Club |
| Theosophical Society in America Headquarters |
| The Richard E. and Charlotte Henrich House |
| The Rockwell House |
| Theurer-Wrigley House |
| Third Church of Christ, Scientist |
| Thomas, F. D., House |
| Thomas, Lewis H., House |
| Thompkins, Jennie S., House |
| Thompson Brothers Rock Art |
| Thompson, James S., House |
| Thorne, George R., House |
| Tiedemann House |
| Tiger-Anderson House |
| Town House, The |
| Town of West Belleville Historic District |
| Townsend House |
| Transfer House |
| Trinity Episcopal Church |
| Tri-Taylor Historic District |
| Trobaugh-Good House |
| Trumbull Park |
| Trustees System Service Building |
| Turkey Hill Grange Hall |
| Turner School |
| Turner Town Hall |
| Turney-Hall House |
| Twin Tower Sanctuary |
| Twiss, James C., House |
| Ulery, Eli, House |
| Union Church |
| Union House |
| Union Lookout |
| Union Park Hotel |
| Union Station |
| Union Trust Bank Company Building |
| Unitarian Church of Urbana |
| United States Custom House |
| United States Post Office and Courthouse |
| United States Post Office and Court House |
| United States Post Office-Belvidere |
| Unity Church |
| Unity Hall |
| University Apartments |
| Upper Bluff Historic District |
| Uptown Broadway Building |
| Uptown Square Historic District |
| Ursa Town Hall |
| U.S. Post Office |
| U.S. Post Office |
| U.S. Post Office and Courthouse |
| Valencia Court Apartments |
| Van Dolah, David Hyatt, House |
| Van Epps, William H., House |
| Van Hagen, George E., House |
| Van Leer, Margaret and Bird, Broadview Mansion |
| Vassar Swiss Underwear Company Building |
| Verdurette |
| Vermont Historic District |
| Vermont Masonic Hall |
| Vesta Accumulator Company Building |
| Vial, Robert, House |
| Victory Sculpture |
| Vienna Public Library |
| Villa Avenue Train Station |
| Villa de Kathrine |
| Village Hall |
| Village of Davis Junction Town Hall |
| Villa Historic District |
| Vine-Oakwood-Green Bay Road Historic District |
| Virginia Theater |
| Vogt, Karl, Building |
| Voorhies Castle |
| Vriner's Confectionery |
| Wabash Avenue YMCA |
| Wabash Railroad Station and Railway Express Agency |
| Wagner, Robert, House |
| Waller, William, House |
| Walnut Grove Farm |
| Walser, Joseph J., House |
| Waltmire Bridge |
| Ward Chapel AME Church |
| Ward, Thornton, Estate |
| Warfield, William S., House |
| Warner, Seth, House |
| Warren Commercial Historic District |
| Warren, Edward Kirk, House and Garage |
| Washington Park |
| Washington Square |
| Washington Square Historic District |
| Watseka Union Depot |
| Watson, David and Julia, House |
| Waukegan Building |
| Waukegan Public Library |
| Wayne Village Historic District |
| Wear, Washington C., House |
Data from United States Park Service and Wikidata
